A. Field of the Invention
The device of the present invention relates to a new and improved packing assembly for a reciprocating pump.
B. Description of the Prior Art
Reciprocating pumps that are employed to force fluid at a high velocity to a water tube boiler under certain conditions of water treatment and water temperature squeal and eventually start to leak. This deterioration of the packing is a result of high temperatures developed by the high speed at which the pump is reciprocated. Examples of reciprocating high pressure and high velocity pumps of this type are illustrated in U.S. Pat. Nos. 3,558,244 and 3,652,188.
One prior art method of reducing the deleterious effects of rapid reciprocation with the resultant drying of the packing is to apply lubricating oil to the back or dry side of the packing. This stops the squeal and extends the life of the packing; however, these results are only temporary. These deleterious effects are also increased when the packing is used in a pump that is forcing water at near boiling temperatures to boilers. A further result is that the lack of lubrication not only heats the packing but also raises the temperature of the cylinder wall of the pump increasing the risk of damage to the pump.
A further difficulty experienced in prior art reciprocating pumps is that the piston is freely carried on the piston rod and experiences side motion and cocking during operation of the pump. This action is also experienced by the packing holder and contributes to the deterioration of the various components of the packing assembly.